HIV (Human Immunodeficiency Virus) mainly spreads through unprotected sexual contact with an infected person when body fluids such as blood, semen, vaginal fluids, or rectal fluids enter the body through mucous membranes or small cuts. The risk is higher if protection is not used or if either partner has other sexually transmitted infections. To prevent infection, it is important to use condoms correctly every time during sex, limit the number of sexual partners, get regular HIV and STI testing, and ensure that both partners know their HIV status. Avoid sharing needles or sharp instruments. If someone is at higher risk, doctors may also recommend preventive medicines such as pre-exposure prophylaxis (PrEP). Practicing safe sex and regular testing are the most effective ways to reduce the risk of HIV infection.

If a person with HIV has been taking Antiretroviral Therapy (ART) regularly for 5 years, the medicines can remain effective for many years or even lifelong as long as they are taken exactly as prescribed. Resistance usually develops only when doses are missed frequently or treatment is not taken consistently, allowing the virus to multiply and change. With good adherence, regular viral load tests, and follow-up with the doctor, ART can keep the virus well controlled and help the person live a long, healthy life. If resistance ever develops, doctors can adjust the treatment with other effective medicines.